1. Field Of The Invention
This invention relates generally to motor vehicle instrumentation, specifically to a gear selection indicator for manual transmissions.
2. Prior Art
Motor vehicles with manual transmissions are generally not equipped with indicators for indicating the currently selected gear. As a result, drivers will sometimes forget the gear they are using. When they try to shift, they would either select the wrong gear, which may damage the engine, or stir the shift lever around in an effort to decide on which gear to use.
Motor vehicles with automatic transmissions are usually equipped with gear selection indicators, which are typically arranged either on a face plate next to the shift lever, or on the instrument cluster behind the steering wheel.
U.S. Pat. No. 5,070,808 to Poskie (1991) shows a gear selection indicator device for being mounted on an instrument panel. It includes a stationary set of gear selection indicia, a stationary backlight, and a movable mask positioned therebetween. The mask has an aperture thereon, and is connected by a cable to a steering-column-mounted shift lever for movement. Moving the shift lever moves the mask to selectively illuminate different parts of the indicia.
U.S. Pat. No. 3,868,923 to Lambiris (1975) shows a device with a stationary set of gear selection indicia, a movable light attached to a steering-column-mounted shift lever for simultaneous movement, and a stationary bundle of optical fibers extending between the indicia and the light.
Moving the shift lever moves the light to illuminate different parts of optical fiber bundle, which illuminates corresponding parts of the indicia.
U.S. Pat. No. 4,191,064 to Houk et al. (1980) shows a gear selection indicator device for a floor-mounted shift lever. It includes a stationary set of gear position indicia arranged on a face plate mounted around the base of the lever, and a movable light attached to the lever under the face plate. Moving the lever moves the light to selectively illuminate different parts of the indicia.
U.S. Pat. No. 3,643,622 to Cryer (1972) also shows a gear selection indicator device for a floor-mounted shift lever. It includes a display panel mounted at the base of the lever, a single stationary light positioned under the panel, and a movable mask positioned therebetween. The mask is connected to the shift lever, which moves the mask linearly under the panel. The mask is connected to a linear series of detents for locating the gear positions. The detents form part of the electrical circuit of the single light, which turns on and off when the mask is moved from one detent to another.
All prior art automatic transmission shift levers select gears in a linear manner by moving in two directions: fore-and-aft for floor mounted units, and up-and-down for steering-column-mounted units. Accordingly the aforementioned gear selection indicators cannot be adapted for use with manual transmission shift levers, which usually move in six directions in a double "H" pattern.
U.S. Pat. No. 5,017,916 to Londt et al. (1991) shows a shift prompter device for manual transmissions. It includes a multi-function digital display for mounting on the dash board or instrument panel of a vehicle. The display includes up and down indicator arrows which are illuminated for indicating the best time to upshift or downshift, respectively. The last digit of the display is for indicating the target gear for each shift, not the currently selected gear. It is very complicated, and requires the installation of numerous unspecified sensors on the drive train. Therefore, it is not suitable for retrofitting to existing vehicles, especially by untrained end users.